1. Field of the Invention
This invention generally relates to a liquid crystal display device, and more particularly to a liquid crystal display device having a pixel repairing structure.
2. Description of the Related Art
In the manufacturing process of a liquid crystal display (LCD) device, pixel defects are liable to be generated and should be repaired, which causes the manufacturing cost inevitably to be increased. Typically, the pixel defects are divided into white defects and dark defects, wherein the white defects are easily recognized by naked eyes. Therefore, it is preferable that the white defects should be repaired as black defects, which are always dark and not easily recognized by naked eyes.
One of conventional methods for repairing a white defect as a dark defect • is widely used in an LCD device 10 as shown in FIG. 1, in which a pixel electrode 12a has at least one part 13 overlapped with a gate line 14 to form a storage capacitor for enhancing the charge storing capacity between the pixel electrode 12a and a common electrode (not shown). When a white defect is caused by poor contact between the pixel electrode 12a and a switching element 16 or by malfunction of the switching element 16, a short circuit is formed between the part 13 of the pixel electrode 12a and the gate line 14 through a welding point 20 formed by a laser such that the white defect can be repaired as a dark defect. U.S. Pat. No. 6,882,375 B2 issued to Kim on Apr. 19, 2005 discloses that a pixel electrode has a repair member overlapped with a neighboring front gate line.
In addition, some of conventional methods for repairing a white defect as a dark defect are used in an LCD device (not shown), in which a pixel electrode is overlapped with a storage line (also referred to as storage capacitor line) to form a storage capacitor. U.S. Pat. No. 6,855,955 B2 issued to Jeon et al. (hereinafter Jeon) on Feb. 15, 2005 discloses that a pixel electrode is electrically connected to a storage capacitor conductor through a contact hole, wherein the storage capacitor conductor has a repairing portion overlapped with the gate line. When a white defect occurs, the gate line is short-circuited with the pixel electrode through the repair portion such that the white defect can be repaired as a dark defect.
However, in the above-mentioned conventional methods, at least one connecting portion (e.g. the part 13 in FIG. 1, the repair member disclosed by Kim and the repairing portion disclosed by Jeon) electrically connected to the pixel electrode is overlapped with the gate line such that a capacitor is formed between the connecting portion and the gate line and thus increases the capacitive load on the gate line. In particular, when the number of pixels along the gate line is large, the capacitive load of the gate line may become considerable and thus cause the delay of the scan signal transmitted in the gate line.